Effects of local administration of capsaicin on primary afferent nerve and substance P
- VernacularTitle:辣椒素局部用药对初级传入神经和P物质的影响
- Author:
Feng GUO
;
Yunfu ZHAO
;
Xiaozhong JIANG
;
Aizhi GAO
- Publication Type:Journal Article
- Keywords:
capsaicin;
trigeminal neuralgia;
primary afferent nerve;
substance P
- From:
Academic Journal of Second Military Medical University
1981;0(04):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To study the effects of capsaicin applied locally to infraorbital nerve on primary afferent nerve inadult rats. Methods:Capsaicin solution (2% ) was directly applied onto one lateral intraorbital nerve, and the contralateralnerve was used as self-control. Both experimental and control infraorbita1 nerves were observed under electron tnicroscope on3, 7, 14, 21, 28, 35 or 42 d after local administration. Substance P(SP)--like immunoreactive positive granules in both lateralnucleus caudalis spinalis nervi trigemini (CNV) were examined by immunohistochemical method. Results: Degenerated un-myelinated fibers in capsaicin-treated nerves were found under electron microscope, and no myelinated fibers changes werefound. The gray scale value of SP-like immunoreactive positive granules in the experimental side was markedly lower thanthat in the control side (P<0. 01), while no significant difference was observed between different time groups. Conclusion:Local administration of capsaicin can produce selective destruction of unmyelinated fibers in primary afferent nerves, and canreduce the levels of SP in regions of CNV. The results suggest that local administration of capsaicin has potential therapeuticvalue for trigeminal neuralgia.